Cable stripping device



Jan. 29', 1946. J. M. LUCARELLE ET AL, 2,393,919

CABLE ST-RIPPING DEVICE Filed May 11, 1945 4 Sheets-Sheet 1 INVENTQRS(Ase cf? Mliucarelle aYEurZl vi c e Fedeli Jail 29, 1946' .1. M.LUCARELLE ET AL 2,393,919

I CABLE STRIPPING DEVICE 4 SheetS -Sheet s Filed May 11, 1943 INV ENTORSfosepfiML ucarelfc ATTO 1946- J. M. LUCARELLE ET AL 2,393,919

CABLE STRIPPING DEVICE Filed May 11, 1945 4 Sheets-Sheet 4 INVENTORZQJose/26M Lucare [e Patented Jan. 29, 1946 CABLE STRIPPING DEVICE JosephM. Lucarelle and Euripide Fedeli, Bridgeport, Conn.,'assignors toDictaphone Corporation, New York, N. Y., a corporation of New YorkApplication May 11, 1943, Serial N6. 486,502

\ 9 Claims.

The present invention relates to an improvement in cable strippingdevices.

In preparing to attach or install insulated or armored cables comprisinga core of one or more insulated conductors within a sheath, it iscustomary to remove end portions of the sheath to expose predeterminedlengths of the conductors. Sheaths commonly employed in cablemanufacture are made of fabric or rubber, or a combination thereof, withvarying compositions and thicknesses for diflerent contemplated uses: Anessential consideration in cable stripping is that the end sections ofsheath be removed without injury to the conductors or their protectivecoverings, as by cutting or abrasion thereof.

An objectof the present invention has been to provide cable strippingapparatus of simple and durable construction and which, in use, permitsexpeditious and controlled cutting of a sheath of any usual compositionor thickness and removal of an end portion thereof without injury to theunderlying conductors or wires. A further object has been to provide acable stripper wherein the sheath is cut by one instrumentality and theincision so made is engaged by another in effecting removal of the endsection of sheath, thereby avoiding undue strain on the cutter andproviding more effective separation of said out off end portion.

Other objects and advantages in construction and use will appear fromthe following description of a preferred embodiment together with theappended drawings, wherein:

Figure 1 is a plan view;

Figure 2, an enlarged end view from the line 2--2 of Figure 1;-

Figure 3, a longitudinal vertical section on the line 3-3 of Figure 2;

Figure 4, a horizontal section on the line 44 of Figure 2;

Figure 5, a view partly in transverse section on the line 5-5 of Figure4;

Figure 6, a transverse vertical section on the line 6-6 of Figure 1;

Figure 7, an enlarged transverse vertical section on the line 'l! ofFigure 1;

Figure 8, an enlarged fragmentary view in section on the line 88 ofFigures 1 and '7;

Figure9, an enlarged fragmentary plan view of a portion of theoperatingxarm and clamping and differential spacing .or stop devicesassocivertical the parts when the cable sheath is cut;

Figure 10, a similar view of the partsshown in Figure 9 but with thespacer finger deflected from spacing position; and

Figure 11, a fragmentary view in section illustrating engagement of thestripper flange with an annular incision in a cable sheath.

As seen in Figure 1, one form of cable stripping apparatus according toour invention and suitable for hand operation is mounted on a workbench, for example, with the sheath cutting and stripping unit at oneend and the cable clamping and moving devices conveniently adjacentthereto.

A typical stripping operation involves the steps of cutting an annularincision through or nearly through the cable sheath at a predetermineddistance from the end to be stripped. The cable is then moved lengthwiseto bring said incision into position to be engaged by suitable strippingmeans. While the severed end portion of the sheath is thus engaged andanother portion of the cable is firmly clamped to an operating lever,the operator swings said lever in a direction to pull the cable awayfrom the stripper and thus dislodge and separate the severed end portionof the sheath from its underlying core.

The sheath cutting and stripping unit, as shown in Figure 3, forexample, includes a bracket I to which is secured a cable guiding .andcutter supporting member including a sleevel2 hav- 7 ing a centralopening .and a terminal annular flange 3. The central opening receives aremovable bushing 4 which is interchangeable with others having bores ofdiiferent diameters so that cables of correspondingly differentdiameters may be received and held in proper operative relation to thecutting and stripping devices. A set screw 5 releasably secures thebushing 4 in operative position.

A rotatable cutter head .6 is mounted at the flanged end of thesupporting sleeve 2 and concentrically with the bore of bushing Gtherein, where it is held in position by a collar I. Said head 6 has acentral recess in its outer face to accommodate the flange 3 and asheath cutter 8 and is rotated manually by means of a crank handle 9extending from its periphery.

The cutter 8, Figure 5, is secured at the inner end of a carrier in theform of a frame or slide 10. Where the cutter is a conventional singleedge safety razor blade 8, as shown, an inner end portion of the slide10 is cut away, Figure 4; and the blade 8 is disposed in the recess thusformed. Blade 8 is assembled with thesllde HI and secured thereto byscrews engaging notches provided at opposite side edges of said blade.

Whe e said blade has an intermediate perforation, as H, Figure 5, theslide is provided withplane.

In the embodiment shown in the'drawings, end

through which headed bolts !5 are passed and secured in head 6 to retaincompression springs 16 in operative position between said extension I 3r and said bolt heads. Slide l0 and'cutter 8 thereon are thus normallybiased inwardly or toward cutting position by said springs IS.

The slide I0 is also provided with a cutter position adjusting screw i!threaded into the lefthand end of slide It], as seen in Figure 5, andextending through the outer portion of said slide so as to project intoa rectangular opening Iii formed within said slide. Screw I! is radiallymounted with respect to the axis of said cutter head 6 to permit radialadjustment of said slide [0 toward and away from said axis. A cam plateI9 is pivotally mounted upon a shoulder screw I9, which extendsoutwardly from the outer face of'head 6 so as to intersect at rightangles the extended axis of the adjustment screw IT. This cam plate isprovided with an eccentric cam portion I8 positioned within the openingID of said slide [0 in such relation to the screw I! that the ported inguides at both sides of the cutting plate 22 covers only a portion ofthe front area of head 6. This leaves space opposite the straight edge24 thereof to receive and actuate the cam --plate 19 and lever 20. V 7

End plate 22 also supports cooperating stripper plates 25 and 23, endportions of which are pivotally secured thereto at 21 and 23respectively. Pins 29 extending outwardly from end plate 22 engage slots30 in'said'stripper plates.

to limit angular movement thereof away from stripping position. Midportions of said stripper plates are engaged and held in position onsaid end piece 22 by a retaining and guide plate BI.

Friction detents 32 mounted in recesses in head 6 engage shallow notchesin the under surface of said stripper plates to releasably retain thelatter in closed or stripping position during the stripping operation tobe described.

Opposed inner edge or face portions of said stripping plates 25 and 26are cut away to form semi-circular notches, the'edges of which arereduced to provide a narrow annular flange33, Fi ure 4,'when said faceportions are brought together.

. ter an annular incision previously made by the latter serves as a camfollower for the purpose of effecting reciprocatory movement of saidslide in said head 5. The inner end of screw I! is held resilientlyagainst the periphery of cam is by the springs l6; and the cam may bemanually adjusted aboutits axis by means of a lever or operating handle20. By adjusting the position of said screw endwise the inner positionof the slide in the groove and therefore the cutting position of blade 8can be accurately and readily set to accommodate any usual sheaththickness. When lever 20 is rocked from the down position, Figure. 2, tothe up position, Figure 5; for example, eccentric, cam I8 is rotated ina man- "ner to permit movement of slide it). and blade 8 inwardly fromretracted position to sheath cutting position where they are yieldinglyheld by pressure of the springs 16. Head 6 may then be rotated manually360 by means ofhandle 9 to cause bladef'8 to produce an annular incisionin a predetermined portion of the sheath or outer covering of .a cable 2I.

Inasmuchas the thickness of the sheath or outercoverof differentcablesof approximately the same diameter may vary, it is desirable to.accurately control the depth of incision for any given run or type ofcable so'that thecutter will not injurethe insulation of the conductorwires.

This control is adequately provided by the above described slideandcutter adjusting and actuating'devices. By rocking lever 20 back fromits sequent stripping step.

As shown in Figures 3 and 4, an end plate 22 is secured to head 6. Saidplate has a guide hole 2310f approximately'the same diameter as andcoaxial with the bore of bushing 4. Thus, when head 6 is rotatedin-cutting, the cable end issup- 75 cutter 8but is preferably notadapted to effact any cutting in addition ,thereto.

Flange 33 is also of a depth sufficient to extend into said incisionwithout, however, tightly gripping the cable core. The latter maytherefore readily be drawn by suitable means through the opening definedby said annular flange 33 while the'severed sheath is held against suchmovement and. is consequently stripped from'the core end. V As shown inFigures 1, 6,-7 and 8, a portion of cable 2| may be'secured in a clampcomprising a lower jaw 34; an upper jaw 35 and a locking lever 33pivoted to said upper'jaw and having an end cam which engages and rideson'a cross piece 49 when'the locking lever is'moved to locking position.The cable engaging part of lower jaw 34-has a raised portion 31, Figure8, and upper. jaw 35 has arecess 38 opposite said raised and thusprevent endwise slippingv when the clamp is actuated to move said ,cablein the stripping'step. 7 r A Said lower clamp jaw 34 is secured on anoperating arm 39 which is pivoted on a bolt 40, Figure-7, at its innerend. Intermediate portions of arm 39 slidably engage a rail platesecuredto the work bench. A stoplug' 42 extends upwards from the top face ofrail plate 4| and between saidv operating arm and the previouslydescribed cutting and stripping unit at the adjacent end of the bench.

As shown in Figures 9 and 10, arm 39 carries a spacing finger 43 pivotedon a stud 44 and with a free end portion interposed between the adjacentface of said arm and the stop lug 42, said finger being provided with anoperating handle 7 48. Said free end of finger 43 supports a'rotat- Vably adjustable spacing piece 45 presenting a helical contact faceadapted to engage the stop '42 when the parts are in the relativepositions .shown in Figure 9. By adjusting said spacing piece to bringone portion or another of said helical face into 'stop engagingposition, theief- Said flange 33 is narrow enough to en-- i'ectivethickness of the spacing member maybe accurately varied within practicalworking limits. A set screw 46 secures said spacing piece 45 in anydesired position of adjustment in relation to finger 43. A stop pin 41extending from finger 43 is positioned to rest on one portion of theupper surface of arm 39 to support said finger 43 and spacing piece 45in operative spacingvposition when disposed as in Figure 9, and bears onanother portion of said upper surface of arm 89 to support the free endof finger 43 and spacing piece 45 out of operative position when theparts are disposed as indicated in Figure 10.

In utilizing the cable stripping apparatus hereinabove described, thatend of a length of cable from which an end portion of the sheath is tobe removed is inserted through the bore of bushing 4 and through andbeyond the hole 23 in end plate 22 to a predetermined extent in relationto blade 8; Thus, if the length of sheath to be removed is five inches,the end face of the cable will be extended to a point five inches fromthe plane of said blade. The cable is secured in this position byswinging lever 36 and top clamping jaw down to the locking positionshown in full line, Figure 6, as previously described, at which time thefinger 43 also occupies the spacing position shown in full line in saidfigure and in Figure 9. i

The cutter operating lever arm 20, Figure 2, is swung clockwise torelease blade 8 into the cutting position shown in Figure 5. Head 6 withthe cutter and other attached parts is rotated one turn by handle 9which produces an annular incision of the required depth in the sheathof cable 2|. Later separation of the severed projecting end of thesheath is facilitated by giving it a slight twist by hand to thus morecompletely detach the cut section from the remainder of the sheath.

Operating lever 20 and connected parts are now returned to their initialpositions -to retract blade 8 from its cutting position and thus todisengage cable 2 I.

Handle 48 is now moved to swing the spacing finger 43 upwardly from fullline position, Figures 6 and 9, to the position shown in Figure 10, andin dotted lines, Figure 6. This displaces the spacinf-i. piece 45 inrelation to stop 42 so that operating arm 39 may now be moved from itscutting position, Figure 9, to its stripping position, Figure 10, where,it is stopped by lug 42. Said movement advances the incision made bycutter 8 into position to be engaged by the reduced annular edge 33 ofthe stripper plates 25, 26 when these are moved to bring their opposedfaces together, Figure 11.

To effect stripping, the outer end of operating arm 39 is actuated toswing in the direction of the arrow, Figure 1. In so doing, cable 2|clamped thereto is drawn away from the strip per plates 25, 26 until theshort end section of the sheath intercepted by the annular strippingflange 33 is completely separated from the remainder of the cable.'I'he'stripper plates 25, 26 are thereafter moved apart to condition thedevice to receive the next cable length; and the stripped cable isdisengaged from the clamp.

The procedural steps above set forth can be performed rapidly andefilciently by one or two operators. Proper use of the describedapparatus insures uniform and efiective cable stripping with minimumlikelihood of damage to the conductors. Favorable results in use areenhanced by the described features of adjustment whereby regulation of.thedepthoi' lncision is controllable to any desired degree of accuracy,and whereby the extent of endwise move ment of the cable from cutting tostripping position may be accurately adjustedto'compensate for changesin the spacing between the ter and the stripping flange.

As various embodiments may be made of the above invention and as changesmight be made in the embodiment above set'tforth, it is to be understoodthat all matter hereinbefore set forth or shown in the accompanyingdrawings is to be interpreted as illustrative and not in a limitingsense.

We claim: l

1. Cable stripping apparatus comprising a rotatable head, a cuttermounted thereon and adju'stable toward and from a position to cut anannular incision in the sheath of a length of cable, guide means adaptedand positioned to hold a length of cable with an end portion extendingacross the path of rotation of said cutter, sheath stripping meansspaced from said cutter and normally disengaged from said cable, meansfor moving said stripping means into operative sheath strippingengagement with the cable, means for clamping the cable, and means formoving the clamping means and the cable away from the sheath strippingmeans.

2. Cable stripping apparatus comprising a rotatable sheath cutter,sheath stripping means spaced from the plane of rotation of said cutter,an operating arm movable toward and from said cutter, a ,cable clampmounted thereon, a stop cutarranged in the path of movement of said arm,

and a spacing member mounted on said arm and movable into and out ofposition between said arm and said stop.

3. Cable stripping apparatus comprising a rotatable sheath cutter,sheath stripping means spaced from the plane of rotation of said cutter,an operating arm movable toward and from said cutter, a cable clampmounted thereon, stop means arranged in the path of movement of saidarm, and means cooperating with said arm and said stop to vary the stopposition of said arm in relation to said cutter.

4. Cable stripping apparatus comprising a rotatable head, a cuttermounted thereon adapted to cut an annular incision in the sheath of acable extending coaxially through said head. sheath stripping meansspaced a predetermined distance from the plane of rotation of saidcutter and cable gripping means positioned on the opposite side of saidcutter from said stripping means and movable said predetermined distancetoward said cutter and stripping means adapted to grip the cable andmove same longitudinally after the sheath cutting operation saidpredetermined distance toward said stripping means.

5. Cable stripping apparatus comprisinga rotatable head, a cuttermounted thereon adapted sheath stripping means" spaced a predetermineddistance from the plane of rotation of said cutter, and means forgripping the cable and movin same longitudinally after the sheathcutting operation said predetermined'distance toward said strippingmeans, said stripping means comprise ing a pair of members movabletransversely to open and closedpositions with respect to said cable andhaving respectively notched portions adapted to penetrate said incisionwhen in closed 7 position.

V 7. Cable stripping apparatus comprising a rigid guide member and arelatively rotatable guide member for receiving spaced portions of alength of cable, .a cutter head movable with said rotatable'guide memberabout the axis of said cable, acutter carrier movably mounted on saidcutter head for radial movement with respect to said axis, a sheathcutter mounted on said carrier between said guides, means for movingsaid carrier in relation to said head to effect movement of saidrcutterinto and out of cutting position comprising a cam mounted on saidrotatable head for rotative movement about an axis parallel to saidcable axis within'a recessed portion of said rotatable head, andadjustable cam follow ing means on said cutter carrier comprising amember disposed upon the-opposite side of said cam from said axis andadjustable with respect to said carrier toward and away from said axiscable extending coaxially through said head, I to limit-radial movementoi." saidcarrier toward said axis. V I

8. In cable stripping apparatus, in combination, a cutterhead mounted torotate about a rigidly supported length oi cable, a cutter carriermounted in guides on said head to' slide radially into and out ofcutting position, resilient means biasing said carrier toward 'cuttingposition, a cam mounted on said-head to rotate about an axis parallel tothe axis of rotation vof said head and in operative relation tosaid'carrier normally toretain said carrier out of cutting position, andmeans'for turning said cam about its axis to release said carrier foradvance'to cutting position.

9. In cable stripping apparatus, in combination, a cutter head mountedto rotate abouta rigidly supported length of cable, a cuttercarriermounted in guides on said head to slide radially into and out of cuttingposition, resilient means biasing said carrier toward cutting position,a cam rotatably mounted on said head in operative relation to saidcarrier normally to retain said carrier out of. cutting position, meansfor moving said cam to release said carrier for advance to cuttingposition; and adjustable means carried by said carrier for operativeen.- ga'gement with said cam.

JOSEPH M. LUCARELIE. EURIPIDE' FEDELI.

